This is one of the secrets I had with traveling on business. I would take the same flights to Canada every week. United flew the routes, and Air Canada sold seats on those same United flights as codeshares. The airfares between the two were dramatically different, sometimes over $500. Just picked whichever one was cheaper that week but had no impact on my schedule.

I used to @Employees Must Wash Hands: I used the same approach with Air Canada and United. For several years I'd often flown on Air Canada "metal" (planes) from Canada to the USA using United Airlines tickets. The cost was often $200 to $300 less per itinerary. The biggest drawbacks were that it decreased chances for a seat upgrade and could make things very complicated during a trip interruption or cancellation. Despite those inconveniences, it was generally the fairest purchase to charge a client.

I'm not crazy for codeshares, I prefer to book with the carrier driving the plane. It's fine when there's no troubles, but if you have any problem. It's one airline vs another.

Just last week I flew a codeshare (Alaska Airlines codedshared as an AA). AA "requested" seat assignments from Alaska, but Alaska didn't get/process/approve the request. AA had my seats, and Alaska had me as "unassigned." Alaska is the operating carrier, so what they say goes.

I did standby for another fight instead of my husband and I being stuck in middle seats for 5 hours.

It's just annoying, but for a $350 savings, I can deal with it.

I have been doing this for several years. I fly regularly to Hong Kong from LAX and LOVE to fly Cathay Pacific. They charge a LOT more if you purchase directly from them. I can usually save $200-$500 by booking through American Airlines website. I just make sure I choose the route that Cathay flies as a code share and get to enjoy the superior service and aircraft amenities of Cathay while paying American's prices. I have done the same thing when flying to Japan. I either fly JAL through their American code share or ANA through United's code share. Lufthansa can be booked when going to Europe as a Code Share with United as well. I avoid US flag carriers at all cost because of the vast difference in service and the amenities on the planes themselves.

I feel a little dumb saying this, but I'm really understanding how this works.

Say I wanted to fly from Boston to Dublin Ireland. I would choose the date and look for flights leaving that day, but where would I do that?

@dontbemadbrad:

I feel even dumber realizing how little sense the last post made.

I use Kayak, which checks all the airlines, along with other sites that check the airlines (cheaptickets, Orbitz, etc). For several they don't cover directly, you can run a search for them in separate windows. They don't actually sell the tickets, just direct to them, so they don't have anything to lose. I'm studying in Seville this fall, and just a few days ago got tickets for about $900RT from MSP through cheaptickets from Kayak.

sometimes codeshare prices are not different, you would only save a few dollars plus might be cheaper going with the main airline. Jet Airways is the main carrier and Air Canada sold seats for a few dollar more.

Also, for those who want to save a few more bucks, try going to a local travel agent instead of buying from online. Sometimes you would save a few bucks and sometimes a lot - and this isnt advance booking, its the next day booking. I checked all the major sites (ie expedia and the main airline site) and then went to a local agent and found out that it was $25 cheaper ( 1120 vs 1145)

and out of topic here - always compare online vs live person. Dont always assume online is cheaper. Another example, I was ordering pizza hut and got the price online. I decided to call them and it was about $6 cheaper.

I did this the other day with a Lufthansa/United flight from DC to Munich. It definitely wasn't the cheapest flight I could find, but it WAS non-stop.

The only thing I don't know about shopping online is that it's difficult to know when to say "okay, this is the best price" and stop looking.

@HaxRomana: I meant to say "the only thing I don't LIKE about shopping online." Freudian slip, I guess.

I'm flying to Barcelona in November this way... $223 all in from JFK. Booked on Iberia.com, but it's an AA flight.

That was odd... I just booked RDU->SJC R/T on Continental. The best deal (by $200) was a Delta codeshare; I go to book it and Continental errors out on me. I call the help number and they say the flight is sold out. (Odd, since the seat map showed tons of open seats.) CO blames it on DL, saying that they are busy breaking the codeshare agreement, and won't give CO any availability.

I'm getting ready to get annoyed, when she offers to book me on a normal CO set of flights at the same fare, and with a more convenient itinerary. The fare I end up booking on the CO flights isn't available on any website.

Kudos to Continental for backing up their website's fares, even though the routing I originally was trying to book wasn't available.

Codeshares can sometimes be a minor pain in the ass. I was flying back home to St. Louis from Berlin, Germany. I had Berlin-Frankfurt and Frankfurt-Chicago segments on Lufthansa and the Chicago-St. Louis segment on United, on an itinerary purchased from United (the same thing from Lufthansa was a few hundred bucks more). Sometime between me purchasing the ticket and the travel date, United changed my Chicago-St. Louis flight. The departure time was only like 4 minutes later than the original time, but they also changed the flight number. This change apparently never made it to Lufthansa's system, so when I checked in at Berlin at the Lufthansa checkin desk, the agent there had some trouble issuing the boarding pass for my Chicago-St. Louis flight, and I would have to get the boarding pass from a United checkin counter in Chicago. In the end, it didn't matter because my Chicago-St. Louis flight ended up getting canceled due to storms in Chicago, so I had to get placed on the next flight to St. Louis and get a new boarding pass anyways. It's minor inconveniences like that which can turn some away from codeshares, but I would do it all over again if I had to. Lufthansa is a million times better than United, and since Lufthansa does not fly to St. Louis, and United does not fly to Berlin, I'd have to have a codeshare anyways. I will put up with that minor inconvenience for the opportunity to take a transatlantic Lufthansa flight as opposed to a tatl United one.

@komodork: That works for Pizza Hut, but I think pretty much all airlines charge you a fee for booking over the phone. Unless the price difference is more than the fee (which I doubt it would be) you're better off online.

@sirwired: Wow! Just checked the CO website, and they wanted $500 for the routing I ended up with over what I actually paid for it.

My family and I had an interesting experience with a codeshare flight from Hawaii a number of years ago... My mom had a bunch of airline miles with British Airways, which was part of the "oneworld" codeshare alliance. Since American Airlines was also part of the same alliance, we used BA miles on American Airlines to get from Lihue, HI -> O'Hare -> Philadelphia.

The day before we were supposed to leave, we looked at our itinerary and saw we had about a 3 hour delay at O'Hare. We called BA to see if we could change our flight plans to avoid the delay, and they put us on a later flight with only a half hour delay. When we got to the airport at Lihue, they told us that we were still booked for the earlier flight which left hours ago. Three different ticketing agents later and we were told that we would not be allowed on the plane and we would have to contact BA to find out what was going on. My mom did not leave the counter until the agent gave up on the computer and let us board anyway.

@datruesurfer: Oneworld is an alliance of airlines that allow cross-airline mile accrual and redemption. For example, I earn AA miles for flying on Cathay Pacific, Qantas and BA (sometimes, but don't get me started on that).

Codeshare flights are individual flights operated by one carrier, but sold by another with the selling carrier's flight number. I've flown AA flight numbers on Qantas, Cathay and Alaska Air.

Your family had an issue because BA issued the ticket for AAs flights and the AA gate agents didn't want to take responsibility.

@jake.valentine: On the other hand, doing the reverse is ridiculously expensive. I want to fly Shanghai-Tokyo-Chicago-Nashville. Buying the Chicago-Nashville part as a JAL codeshare costs more than 5x what American charges.

I don't really like codeshares sometimes. Like the time I was flying to San Francisco from Vancouver on a supposedly Air Canada flight... then I took a look at the plane and it was United. Oh man.

Yes this works, but there are exceptions.

I've used Kayak before and on routes that United served, Kayak would say that there was a fare available for the United flights on US Airways. US Airways, however, wanted at least maybe $100-$300 more than what United wanted for the flights. (I haven't used Kayak in a while, but I bet this kind of pricing is still going on)

I use adioso.com to find the cheapest fares. It's like Google for flight prices.

@spongebue: Eeek, I still need to get used to this reply system... that was meant to be a new thread

OK, I'll be the next dumb guy and ask: can someone please post a step-by-step HOWTO for this? I'm not a frequent flyer, but would still like to know how this works. I know the idea of a 'codeshare'. I just want to know how does one go about booking codeshare flights.

@spongebue: @YoFonzie:

Again, you're not alone. I don't understand how this is any different from just using Kayak.org which is what I already use to book flights.

How is using codeshares different?

@YoFonzie:

Go to any ticket purchasing website (i.e. Orbitz, Travelocity, Expendia, etc). Look for a flight you want and if it says, for example: "American Airlines 9999 (Operated by Cathay Pacific)" then you know its code share flight. In this example, American Airlines is selling the tickets on a flight operated by Cathay Pacific. The high flight number (9999) sometimes also signifies the flight is code share and not operated by that specific airline.

Then, in this example, go to Cathay Pacific and look for that exact same flight times. That's the corresponding flight. Then, compare prices.

If you want to fly a specific airline but the flight is too expensive, then to to the airline's website and see who their codeshare partners are. Then try looking for your flight through those corresponding airlines.

@doireallyneedausername: Thanks. It's unfortunate that the route I fly isn't covered by any codeshare (United codeshares with ANA up to Tokyo and Shanghai Airlines non-stop to Shanghai from Chicago, but I can't seem to get a Chicago-Tokyo-Shanghai).

@komodork: Also true for rental cars. Online rate with coupon codes: $53.99/day. I called my local Enterprise and asked "What's the best price you can get me for such-and-such a car? $27.99/day. I had no idea car rentals could be so cheap? PS: The $27.99 rate would have gotten me a Pontiac G6, Chevy Malibu, or 4-door Ford F-150 truck.

@jamar0303: That's just it, no airline flies that route all by itself, but you could book the flight 3 different ways:

Book on United
Book on ANA
Book on Shanghai

In any of those cases, probably 2 of the 3 legs would be a codeshare flight. Price your route using each of those 3 airlines and find the cheapest one.

Seems like a LOT of work to get the codeshare thing done, but I can see how the effort might be worth it on long-haul flights.

Let me open up a can'o'worms with this question, though:

Any special reason not to use a travel agent and have them do all the heavy lifting on something like this?

@t325: I second both your points: 1) codeshares can be a major inconvenience when you have layovers and are switching from one airline to another. When Delta got me to Paris too late to make a connection on Air France, there was a lot of finger-pointing and hassle that wouldn't have occurred if my whole trip was with AF.

2) You're flying with whoever actually flies the plane. If you're particularly fond of the service on one airline, it can be disappointing to realize that you're getting something else. But you get what you pay for, and if you know of the codeshare in advance, it might be worth it. For a few transatlantic flights, I've been caught off guard, and it is not fun.

@dontbemadbrad: I use Farecast.com
I like it better than kayak, which it is not bad at all.

@The-Lone-Gunman: It actually isn't that hard at all. Like anything new task you might attempt, it may take a few trips before you have the steps down pat. I just finished booking my next trip to Japan moments ago. It took about 10 minutes total to book the airline I wanted (JAL) using a AA code share. I normally prefer ANA over JAL, but I had to arrive by a certain time. Cost difference was about $300 for a flight in 2 weeks.